Methylamine → 3-[6,7,8,9-tetrahydro-8-[(methylamino)methyl]pyrido[1,2-a]indol-10-yl]-4-(1-methyl-3-indolyl)-1H-pyrrole-2,5-dione hydrochloride

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Reaction Steps

265 mg of trifluoromethanesulfonic anhydride in 40 ml of dichloromethane were treated at 0° C. under a nitrogen atmosphere with a suspension of 200 mg of the pyrroledione product of Example 1 and 100 mg of collidine in 30 ml of dichloromethane. After 5 hours, 0.75 ml of a 33% solution of methylamine in methylated spirit was added and the mixture was stirred for 18 hours. An additional 0.5 ml of the aforementioned methylamine solution was then added. After 4 hours, the solvent was removed by evaporation and the precipitate was filtered off and purified by chromatography on silica gel with dichloromethane/methanol/acetic acid/water (90:18:3:2). The solid product was stirred with ethyl acetate saturated with hydrogen chloride for 2 hours. The resulting solid was filtered off and dried to give 55 mg of 3-[6,7,8,9-tetrahydro-8-[(methylamino)methyl]pyrido[1,2-a]indol-10-yl]-4-(1-methyl-3-indolyl)-1H-pyrrole-2,5-dione hydrochloride of melting point 337°-340° C.

Provenance & Evidence